The Bees almost pulled off one of the shocks of the round when Harry Forrester gave his side the lead from the penalty spot 17 minutes from time, only for Fernando Torres to force a replay 10 minutes later with a fine shot from the edge of the area.

And Donaldson has publicised Ashley Cole’s constant dissatisfaction with his side's attacking movement and the lack of penetration from the strikers as the holders were held by the League One outfit.

"[Cole] was always mumbling something, always mumbling stuff quietly, but I could still hear what he was saying. He was just getting frustrated,” Donaldson told reporters.

"He was saying about the forward players not showing, saying things like 'He needs to be there' and pointing. You could just see straight away that he was getting frustrated. That was a good thing."

The 28-year-old forward also believes that all the pressure is on Rafael Benitez's men in the replay and that Brentford are capable of exploiting any weaknesses after their strong showing on Sunday, especially if the home fans continue to protest against the Blues’ interim boss.

He continued: "We are confident. That [atmosphere at Stamford Bridge] has played a part in their recent form. Obviously the fans are unhappy with the manager – they don't really like him – so any little thing that goes wrong, they're always on their backs.

"I think that has played a part in their recent results so, hopefully, we can put that to our advantage and the take the positives and unrest their fans again at their place. You couldn't really see that they were European champions. We set out to unsettle them, and we did that.

"They didn't really create that many chances, which I am very surprised about to be honest, especially with the quality of players they have got. That was down to our hard work. We'd done our homework on them and we stopped them creating. We have to take some credit for that.

"We're confident, especially given their run of form at home recently not having been the best. The pressure will be on them again."